Antiarrhythmic agents can induce severe hypotension (particularly with IV administration) or induce or worsen congestive heart failure (CHF). Patients with primary cardiomyopathy or inadequately compensated CHF are at increased risk. Antiarrhythmic agents should be administered cautiously and dosage and/or frequency of administration modified in patients with hypotension or adequately compensated CHF. Alternative therapy should be considered unless these conditions are secondary to cardiac arrhythmia.

Antiarrhythmic agents can induce or worsen ventricular arrhythmias. Ventricular tachycardia, ventricular fibrillation, and torsades de pointes have occurred in some patients. Patients with underlying cardiac dysfunction, bradycardia, hypokalemia, hypomagnesemia, or high antiarrhythmic serum concentrations are at increased risk for drug-induced arrhythmias. Therapy with antiarrhythmics should be used with extreme caution in patients with or predisposed to arrhythmias. Evidence of improved survival is lacking for use of antiarrhythmic therapy in asymptomatic, non-life-threatening arrhythmias. Therapy with antiarrhythmic agents should be reserved for patients with life-threatening arrhythmias.

Potassium chloride liquid suspension contains the stool softener, docusate sodium, as a dispersing agent. Clinical studies with potassium chloride liquid suspension indicate that minor changes in stool consistency may be common though usually well tolerated. However, patients may rarely experience diarrhea or cramping abdominal pain. Patients with severe or chronic diarrhea or who are dehydrated ordinarily should not be prescribed potassium chloride liquid suspension.

References

Potassium Salts (Includes Lidocaine/potassium chloride) ↔ Dehydration

Severe Potential Hazard, High plausibility

Applies to: Dehydration, Diarrhea

Administration of potassium salts in severe dehydration may predispose to renal impairment. Therapy with potassium salts should be administered cautiously in patients with acute dehydration (e.g., due to severe or prolonged diarrhea or heat stress). Close monitoring of serum potassium concentrations is recommended, as potentially fatal hyperkalemia can develop rapidly and is often asymptomatic, manifested only by an increased potassium level (6.5 to 8 mEq/L) and characteristic electrocardiographic changes (peaking of T waves, loss of P waves, depression of ST segment, prolongation of the QT interval). Late manifestations include muscle paralysis and cardiovascular collapse from cardiac arrest (9 to 12 mEq/L). Continuous or serial electrocardiography may be appropriate in some patients during replacement therapy, particularly if given intravenously.

Administration of potassium salts may precipitate attacks in familial hyperkalemic periodic paralysis or paramyotonia congenita. Therapy with potassium preparations should be administered cautiously in patients with these conditions.

The use of potassium salts is contraindicated in patients with hyperkalemia, since a further increase in serum potassium concentration in such patients can lead to cardiac arrhythmias or arrest. Potassium therapy should be administered cautiously in patients with conditions predisposing to hyperkalemia, such as chronic renal failure, systemic acidosis, acute dehydration, hypoaldosteronism (e.g., due to primary adrenal insufficiency or congenital adrenal enzyme deficiency), uncontrolled diabetes mellitus, and extensive tissue breakdown (e.g., due to severe burns, intravascular hemolysis, tumor lysis syndrome, or rhabdomyolysis). Close monitoring of serum potassium concentrations is recommended, as potentially fatal hyperkalemia can develop rapidly and is often asymptomatic, manifested only by an increased potassium level (6.5 to 8 mEq/L) and characteristic electrocardiographic changes (peaking of T waves, loss of P waves, depression of ST segment, prolongation of the QT interval). Late manifestations include muscle paralysis and cardiovascular collapse from cardiac arrest (9 to 12 mEq/L). Continuous or serial electrocardiography may be appropriate in some patients during replacement therapy, particularly if given intravenously.

The use of potassium salts is contraindicated in patients with severe renal impairment characterized by oliguria, anuria, or azotemia. Since potassium is excreted by the kidney, the administration of potassium salts in such patients, particularly by the intravenous route, may produce hyperkalemia and cardiac arrhythmias or arrest. Therapy with potassium salts should be administered cautiously in patients with diminished renal function or other conditions which impairs potassium excretion (e.g. adrenal insufficiency). Close monitoring of serum potassium concentrations is recommended, as potentially fatal hyperkalemia can develop rapidly and is often asymptomatic, manifested only by an increased potassium level (6.5 to 8 mEq/L) and characteristic electrocardiographic changes (peaking of T waves, loss of P waves, depression of ST segment, prolongation of the QT interval). Late manifestations include muscle paralysis and cardiovascular collapse from cardiac arrest (9 to 12 mEq/L). Continuous or serial electrocardiography may be appropriate in some patients during replacement therapy, particularly if given intravenously.

The use of all solid oral formulations of potassium is contraindicated in patients with arrested or delayed gastrointestinal (GI) transit, whether due to structural, pathological, or pharmacological causes. Potassium is irritating to the GI mucosa and may cause ulcerative and/or stenotic lesions during prolonged physical contact. Based on spontaneous adverse reaction reports, the frequency of small bowel lesions associated with enteric-coated preparations of potassium chloride is 40 to 50 per 100,000 patient-years, while that for wax matrix controlled-release formulations is less than one per 100,000 patient years. Esophageal ulceration has also been reported following administration of controlled-release formulations of potassium chloride in cardiac patients with esophageal compression due to enlarged left atrium. Potassium supplementation should be administered as a liquid preparation or as an aqueous suspension in patients with esophageal obstruction and/or delayed gastrointestinal transit time.

Because of ulcerogenic effects, oral potassium should be administered cautiously in patients with peptic ulcers or other upper gastrointestinal diseases associated with inflammation, bleeding, or perforation. Patients should be advised not to crush, chew, or break potassium tablets or capsules, and to take them with meals and a full glass of water or other liquid. Potassium liquids should be diluted prior to consumption.

Electrolyte imbalance can alter the therapeutic effectiveness of antiarrhythmic agents. Hypokalemia and hypomagnesemia can reduce the effectiveness of antiarrhythmic agents. In some cases, these disorders can exaggerate the degree of QTc prolongation and increase the potential for torsades de pointes. Hyperkalemia can potentiate the toxic effects of antiarrhythmic agents. Electrolyte imbalance should be corrected prior to initiating antiarrhythmic therapy. Clinical monitoring of cardiac function and electrolyte concentrations is recommended.

Potassium Chloride (Includes Lidocaine/potassium chloride) ↔ Acidosis

Moderate Potential Hazard, High plausibility

Applies to: Acidosis

Hypokalemia in patients with metabolic acidosis should be treated with an alkalinizing potassium salt (i.e. acetate, bicarbonate, citrate, or gluconate) rather than potassium chloride, since alkali therapy helps to promote cellular uptake of potassium. Close monitoring of acid-base balance, serum electrolytes, electrocardiogram, and clinical status is recommended.

Do not stop taking any medications without consulting your healthcare provider.

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